In a near repeat of Tuesday's Premier League game between the sides, which Villa won 2-1, Fabian Delph and Scott Sinclair struck to take Tim Sherwood's team into the last four for the first time since 2010.

Both teams finished the game with 10 men, with Claudio Yacob sent off for West Brom and Max Grealish dismissed for Villa, while play had to be temporarily suspended late on when a number of home fans poured onto the pitch.

Delph described the pitch invasion, which was repeated at full-time, as "scary" and said he had been bitten by some of the invading supporters, while West Brom manager Tony Pulis described the scenes as "disgraceful".

But Villa manager Sherwood said: "I don't think it's scary. It probably is for a West Brom player. Emotions are running very high after two wins and it's been a huge week for the football club."

Giant-killers Bradford City had earlier been taken to a replay by Reading. Liverpool host Blackburn Rovers on Sunday and holders Arsenal travel to Manchester United in the tie of the round on Monday.

Ben Foster and Christian Benteke had been the central figures in Villa's win over West Brom on Tuesday, with the former conceding the stoppage-time penalty from which Benteke scored the winning goal.

But neither player was present for the reunion, with Boaz Myhill replacing Foster in the West Brom goal and a hip injury obliging Benteke to cede his place to Sinclair.

Pulis led Stoke City to the final in 2011 and his current charges made an enterprising start, with Saido Berahino working Shay Given before Brown Ideye somehow contrived to lift Craig Gardner's inviting cross over the bar.

But it was Villa who drew first blood in the 51st minute when Delph collected a pass from Charles N'Zogbia and bludgeoned a low shot inside Myhill's near post.

- Physical encounter -

Six minutes later, West Brom procured a glorious opportunity to equalise, but Joleon Lescott could only head wide at the back post after Villa midfielder Tom Cleverley had helped on Gardner's left-wing corner.

Yacob was sent off after being shown a second yellow card for a fairly innocuous block challenge on Leandro Bacuna, and Sinclair sealed the visitors' fate by curling home five minutes from time.

Grealish's dismissal was similarly contentious, the Villa substitute earning a second booking for a less than clear-cut dive, and the pitch invasions brought matters to an unsavoury conclusion.

Third-tier Bradford's extraordinary progress through the competition was suspended at the quarter-final stage after they were held to a 0-0 draw by Championship side Reading.

Bradford memorably came from 2-0 down to win 4-2 at Chelsea in the fourth round before eliminating Sunderland in round five, but they found Reading a tougher proposition at a muddy Valley Parade.

Bradford manager Phil Parkinson, who spent 11 years at Reading as a player, praised his side, telling BT Sport: "They were very professional and made sure we stayed in the game.

"I thought we got a bit of momentum in the second half and were the team in the ascendancy. We look forward to the replay."

Bradford, beaten League Cup finalists in 2013, are attempting to reach the semi-finals for the first time since they won the trophy in 1911, while Reading last made the last four in 1927.

An uneven, sun-baked playing surface contributed to a bruising, physical encounter beneath the Yorkshire sunshine, as players from both sides struggled to keep the ball on the ground.

Both teams struck the woodwork in the first half, with Reading striker Pavel Pogrebnyak hitting the left-hand post from Jamie Mackie's cross before Gary Liddle's effort drifted against an upright at the other end.